The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Image guided medical and surgical procedures utilize patient images obtained prior to or during a medical procedure to guide a physician performing the procedure. Recent advances in imaging technology, especially in imaging technologies that produce highly-detailed, two, three, and four dimensional images, such as computed tomography (CT), magnetic resonance imaging (MRI), fluoroscopic imaging (such as with a C-arm device), positron emission tomography (PET), and ultrasound imaging (US) has increased the interest in image guided medical procedures.
Typical image guided navigation systems generally require dynamic reference frames to track the position of the patient should patient movement occur during the assisted procedure. The dynamic reference frame is generally affixed to the patient in a generally permanent or immovable fashion. The dynamic reference frame may also be used as a fiducial marker and may, therefore, be attached to the patient during the acquisition of pre-operative images. This enables the image space to be aligned with patient space during the navigated procedure. Generally, during the navigated procedure, images are taken by a suitable imaging device to update the patient space (in the case of patient movement) and/or update the tracking of a navigated instrument.
In order to properly correlate the intra-operative images with the pre-operative images, the navigation system needs to be aware of the activation and deactivation of the imaging device. For example, in the case of a fluoroscopic C-arm x-ray imaging system, radiation sensors can be used to determine if the C-arm is actively imaging. The use of radiation sensors can be undesirable in cases where large bodies absorb the radiation generated by the C-arm, and thereby inhibit detection of the generated radiation by the radiation sensors. Accordingly, it can be desirable to provide a system and method for detecting the operational status of the imaging device.